1. Field of the Invention
The present invention relates to a liquid crystal display device, and more particularly to a technique which is effectively applicable to a control of a coating region of an orientation film.
2. Description of the Related Art
Conventionally, as a display device which displays a video or an image, there has been known a liquid crystal display device which uses a liquid crystal display panel sealing a liquid crystal material between a pair of substrates.
In the liquid crystal display panel, on one substrate out of a pair of substrates, for example, a plurality of scanning signal lines and a plurality of video signal lines are formed. Then, a region which is surrounded by two neighboring scanning signal lines and two neighboring video signal lines corresponds to one pixel region, and a TFT element, a pixel electrode and the like are arranged on each pixel region. This substrate is generally referred to as a TFT substrate. Further, another substrate which forms a pair with the TFT substrate is generally referred to as a counter substrate.
When the liquid crystal display panel adopts a vertical-electric-field method such as a TN method or a VA method, for example, a counter electrode (also referred to as a common electrode) which faces the pixel electrodes of the TFT substrate in an opposed manner is arranged on the counter substrate side. Further, when the liquid crystal display panel adopts a drive method which is referred to as a lateral electric field method such as an IPS method, for example, the counter electrode is arranged on the TFT substrate.
Further, the TFT substrate and the counter substrate form an orientation film thereon for controlling the direction (orientation) of liquid crystal molecules in a state that no potential difference exists between the pixel electrode and the counter electrode and an arrangement and an inclination of the liquid crystal molecules when the potential difference is generated between the pixel electrode and the counter electrode.
The orientation film is formed on an interface with a liquid crystal material (a liquid crystal layer) of each substrate and, for example, is formed by applying rubbing treatment to a surface of a resin film made of polyimide which is formed to cover the whole display region constituted of a mass of the pixel regions.
Further, a resin film which is formed on surfaces of respective substrates is conventionally formed by a method which is referred to as an aniline printing method, for example. However, recently, there has been proposed a method which uses an inkjet printing method (for example, seethe following patent document 1). The ink jet method can directly perform drawing on a substrate and hence, the ink jet method has various advantages such as the low contamination attributed to a non-contact process, the reduction of a solution consumption quantity and the shortening of an initial setup time.
Patent document 1: JP-A-2001-337316